System for anchoring medical devices

ABSTRACT

Some embodiments of a medical device anchor system include an anchor device that receives a catheter (or other medical instrument) and secures the catheter in place relative to a skin penetration point. In some embodiments, the anchor device can secure the catheter in an operative position relative to the skin without the use of sutures or skin tapes. In particular embodiments, the anchor device can be adjusted to a folded condition so that subcutaneous anchors are partially rotated prior to removal from the skin penetration point.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This is a division U.S. patent application Ser. No. 13/672,882 filed onNov. 9, 2012 by Rosenberg et al., which is a division U.S. patentapplication Ser. No. 12/367,164 filed on Feb. 6, 2009 by Rosenberg etal. The entire contents of these previous applications are incorporatedherein by reference.

TECHNICAL FIELD

This document relates to an anchor device, such as a device for use insecuring the position of a catheter or another medical instrument.

BACKGROUND

Venous, arterial, and body fluid catheters are commonly used byphysicians. For example, such catheters may be used to gain access tothe vascular system for dialysis, for introducing pharmaceutical agents,for nutrition or fluids, for hemodynamic monitoring, and for blooddraws. Alternatively, catheters can be used for drainage of fluidcollections and to treat infection. Following introduction into thepatient, the catheter is secured to the patient. In conventionalpractice, the catheter is commonly secured to the patient using anadhesive tape on the skin or by suturing a catheter hub to the patient'sskin.

SUMMARY

Some embodiments of a medical device anchor system include an anchordevice that receives a medical instrument (such as a catheter or thelike) and secures the instrument in place relative to a skin penetrationpoint. In some circumstances, the anchor device can be actuated so thatsubcutaneous anchors are inserted through the skin penetration pointthat is already occupied by the medical instrument. Such a configurationmay allow the anchor device to be used after medical instrument isalready in place without the need for a second penetration point for theanchor device. In particular embodiments, the anchor device may have apivoting design for the subcutaneous anchors so as to facilitate removalof the device and reduce trauma to surrounding tissue near thepenetration point. For example, the anchor device can be adjusted to afolded condition so that the subcutaneous anchors are partially rotatedprior to removal from the skin penetration point. In thesecircumstances, the subcutaneous anchors can be contemporaneously removedfrom the skin penetration point with an upward withdrawal force in amanner that reduces the likelihood of damage to the tissue surroundingthe skin penetration point.

In some embodiments, an anchor device for securing the position of acatheter can include a retainer body to releasably couple to thecatheter. The retainer body may include a first body portion that ispivotably coupled to a second body portion. The anchor device may alsoinclude first and second anchors that extend distally from the retainerbody. Each anchor may include a flexible tine that is deployable in asubcutaneous region to secure the retainer body relative to apenetration point. The first anchor may be coupled to the first bodyportion and the second anchor being coupled to the second body portion.The first body portion of the retainer body may be pivotable relative tothe second body portion so that the first and second anchors areadjustable from a deployed configuration in which the flexible tinesextend generally away from one another to a removal configuration inwhich the flexible tines extend generally in the same direction.

In further embodiments, an anchor system for securing the position of amedical instrument can include a delivery device and an anchor device.The delivery device can advance the anchor device toward a skinpenetration point that is occupied by the medical instrument. Thedelivery device may define an internal space and a distal opening. Theanchor device may be deployable from the internal space of the deliverydevice. Also, the anchor device may comprise a retainer base toreleasably secure with the medical instrument. The anchor device mayfurther comprise one or more subcutaneous anchors that extend distallyfrom the retainer base and toward the skin penetration point when thedelivery device deploys the one or more subcutaneous anchors from thedistal opening. Each anchor may include a tine that deploys in asubcutaneous region to secure the retainer base relative to the skinpenetration point. Also, each tine may be pivotable about a longitudinalaxis from a deployed configuration to a removal configuration.

Some embodiments of a method of using a catheter anchor device mayinclude advancing a catheter though a skin penetration point anddirecting an anchor device toward the skin penetration point that isoccupied by a portion of the catheter. Te anchor device may comprise aretainer body to releasably couple to an external portion of thecatheter arranged outside the body, and first and second anchors thatextend distally from the retainer body. The method may further includeinserting the first and second anchors through the skin penetrationpoint that is occupied by the catheter so that at least a portion of thefirst and second anchors are deployed in a subcutaneous region proximatethe skin penetration point. The method may also include securing thecatheter with the retainer body so that the catheter is anchoredrelative to the skin penetration point. The method may further includepivoting the first and second anchors about a longitudinal fold linedefined by the retainer body so that the first and second anchors areadjusted from a deployed configuration to a removal configuration. Themethod may also include removing the first and second anchors from thesubcutaneous region and the skin penetration point.

These and other embodiments may provide one or more of the followingadvantages. First, some embodiments of an anchor system can retain amedical instrument in a desired position relative to a skin penetrationpoint without necessarily requiring sutures or skin adhesives. Second,in some embodiments, an anchor device can include a retention portionthat readily mates with a medical instrument (such as a catheter) and atleast one anchor extending distally from the retention portion to engagethe skin penetration point as the medical instrument. Third, the anchordevice can include one or more anchors configured to deploy in asubcutaneous region under the skin proximate to the skin penetrationpoint of the medical instrument. In such circumstances, the anchors maybe inserted through the skin penetration point in a manner that reducesthe likelihood of trauma to the surround skin tissue. Fourth, in someembodiments, the anchor device may be partially folded or otherwiseadjusted so that the subcutaneous anchors are partially rotated prior toremoval from the skin penetration point. For example, the subcutaneousanchors may include tines that extend outwardly away from one anotherwhen deployed in the subcutaneous region, but can be partially rotatedto extend in a generally side-by-side orientation during removal fromthe skin. In these circumstances, the subcutaneous anchors may bereadily removed from the skin penetration point with a noncomplex upwardforce. Fifth, some embodiments of the anchor device may include adelivery device that facilitates delivery of the anchors toward the skinpenetration point. For example, the delivery device may be configured asa disposable, hand-held actuator that provides for convenient graspingby a user. Moreover, the delivery device can be actuated so as to deploythe anchors into the subcutaneous region before the delivery device isremoved from the anchor device.

The details of one or more embodiments of the invention are set forth inthe accompanying drawings and the description below. Other features,objects, and advantages of the invention will be apparent from thedescription and drawings, and from the claims.

DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view of an anchor device with a portion of thedevice located in a subcutaneous region, in accordance with someembodiments.

FIGS. 2-3 are top and front views, respectively, of the anchor device ofFIG. 1 with the medical device retention portion in an open and deployedconfiguration.

FIGS. 4A-4B are front and rear views, respectively, of the anchor deviceof FIG. 1 with the medical device retention portion in a closed anddeployed configuration.

FIG. 5 is a top view of the anchor device of FIG. 1, with the medicalretention portion removed view.

FIG. 6 depicts a front view of the anchor device of FIG. 1 with theanchor device in a transitional configuration between a deployedconfiguration and removal configuration.

FIG. 7 depicts a front view of the anchor device of FIG. 1 with theanchor device in a removal configuration.

FIGS. 8A-8C depict top, side, and front views of the anchor device ofFIG. 1 in a shipping configuration within a delivery tool, in accordancewith some embodiments.

FIGS. 9-15 are perspective views of an anchor system, including theanchor device of FIG. 1, for use in securing the position of a medicalinstrument.

Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

Referring to FIG. 1, some embodiments of a medical device anchor system10 include an anchor device 100 that releasably retains a medicalinstrument 20 (e.g., depicted as a catheter in this embodiment) in anoperative position relative to a portion of skin 30 (e.g., relative to askin penetration point 32). The anchor device 100 may include a base 110and a cap assembly 130. The base 110 may include a retainer body 111 andone or more anchors 140 a-b that extend distally from the retainer body111 for deployment in a subcutaneous layer 34. The base 110 can receivethe medical instrument 20, and the cap assembly 130 can be removablycoupled to the base 110 to secure the medical instrument 20 in agenerally fixed position relative to the base 110. As described ingreater detail below in connection with FIGS. 2-3, the base 110 and thecap assembly 130 can include gripping members 120 and 135, respectively.When the cap assembly 130 is coupled to the base 110, the grippingmembers 120 and 135 can releasably engage with an outer surface of themedical instrument 20. The medical instrument 20 can extend from thegripping members 120 and 135 and through a penetration point 32 in apatient's skin 30 (e.g., through a small incision, a puncture, or thelike), while the retainer body 111 and the gripping members 120 and 135remain outside of the skin 30.

As described in more detail below, the anchor device 100 can secure thecatheter 20 in the operative position relative to the penetration point32 without necessarily requiring sutures or adhesive tapes bonded to theskin. For example, the base 110 can include the one or more anchors 140a and 140 b that extend distally from the retainer body 111 so as topenetrate through the same skin opening as the medical instrument 20.The anchors 140 a and 140 b can include tines 145 a and 145 b that,after insertion, reside in the subcutaneous region 34 (e.g., a regionunder the dermal layers of the skin 30 that may comprise a fatty tissuelayer) so as to secure the position of the anchor device 100—and themedical instrument 20 retained therein—relative to the penetration point32.

Referring now to FIGS. 1-3, in some embodiments, the medical instrument20 can include a catheter to be inserted through the penetration point32 of the skin 30 as part of a medical procedure. For example, in theembodiment depicted in FIG. 1, a central venous catheter 20 can beinserted into a percutaneous opening surgically formed in the skin(e.g., penetration point 32), to the underside of the skin 30, and intoa vein 40 to provide vascular access for delivering medications orminimally invasive devices into a patient. After placement of thecatheter 20, the base 110 of the anchor device 100 can approach thepenetration point 32 such that the tips 142 of the anchors 140 a and 140b enter the skin 30 through the penetration point 32. As the anchordevice 100 is inserted through the penetration point 32, the tines 145 aand 145 b are stressed to flex against anchor shafts 141 a and 141 b(refer also to FIG. 10) so as to pass through the penetration point 32in a manner that reduces the likelihood of trauma to the surroundingskin tissue. As the anchors 140 a and 140 b are collectively advancedthrough the penetration point 32, the tines 145 a and 145 b are movedbeneath the dermal skin layers 36 of the skin 30. When the tines 145 aand 145 b reach the subcutaneous region 34, the tines 145 a and 145 bare biased to return toward an unstressed shape, as shown in FIG. 2,thereby deploying in the subcutaneous region 34.

Referring now to FIG. 2, the anchors 140 a and 140 b may be designedsuch that the tines 145 a and 145 b include a curvature that abutsagainst the underside of the dermal layers 36 in a manner that reducesthe likelihood of the tine tips 146 puncturing the underside of thedermal layers 36. When the tines 145 a and 145 b of the anchors 140 aand 140 b are deployed in the subcutaneous region 34, the cap assembly130 can be removably coupled to the base 110 (see FIGS. 4A-4B),compressing the securing portions 120 and 135 of the anchor body 100causing the securing portions 120 and 135 to releasably engage with anouter surface of the medical instrument 20. In this way, the anchordevice 100 can be secured to the patient without the retainer body 111penetrating though the skin 30 of the patient and without necessarilyrequiring sutures or adhesive tapes bonded to the skin 30.

In some embodiments, some of which are described in more detail below inconnection with FIGS. 8A-8C and 9-13, a delivery tool 150 that can beused to deploy at least a portion of the anchor device 100 in thesubcutaneous region 34 and can include features that advantageouslycause the tines 145 a and 145 b to flex against anchor shafts 141 a and141 b (refer to FIG. 10) until the tines 145 a and 145 b have passedthrough the penetration point 32, thereby reducing trauma to thesurrounding skin tissue.

Referring now to FIGS. 2-3 and 4A-4B, some embodiments of the anchordevice 100 can include structures designed to mate with portions of themedical instrument 20 to be retained by the anchor device 100. Theanchor device 100 can include the gripping members 120 and 135 used tosecure the catheter 20 (or other medical instrument) relative to theskin penetration point 32. For example, after the catheter 20 isdelivered into the targeted vein 40 (or other bodily lumen) and afterthe tines 145 a and 145 b are deployed in the subcutaneous region 34,the cap assembly 130 can be removably coupled to the base 110,compressing the gripping members 120 and 135 to temporarily engage withthe outer surface of the catheter 20. In this way, the anchor device 100can be transitioned from the open configuration (shown in FIGS. 2-3) tothe closed configuration (shown in FIGS. 4A-4B) to thereby secure thecatheter 20 with the gripping members 120 and 135. As described in moredetail below, the retainer body 111 can include locking tabs 112 thatcan pass through openings 132 in the cap 131 and positively engage atleast a portion of perimeters 134 of the openings 132, thereby removablycoupling the cap assembly 130 to the base 110.

Still referring to FIGS. 2-3 and 4A-B, the anchor device 100 can includefeatures that facilitate separation from the catheter 20, which canpermit the catheter 20 and anchor device 100 to be removed from the skin30 independently of each other. For example, the tabs 112 may bedisengaged from the cap assembly 130 to decouple the cap assembly 130from the base 110. Once the cap assembly 130 is removed, the grippingmembers 120 and 135 can release from the catheter 20, thereby allowingthe catheter 20 to be moved relative to the anchor device 100. As such,the catheter 20 can be moved independently from the anchor device 100,for example, to withdraw the catheter 20 from the patient while at leasta portion of the anchor device 100 remains secured to the skin 30.

Some embodiments of the anchor device 100 can include structuresconfigured to mate with portions of the medical instrument 20 to beretained by the anchor device 100. For example, when the anchor deviceis in the closed configuration (as depicted in FIGS. 4A-4B), thegripping members 120 and 135 can define a channel 122 that extendslongitudinally from the proximal portion 103 of the anchor device 100toward the anchors 140 a and 140 b. The channel 122 can be configured tocomplement an outer surface of the catheter 20 or other medicalinstrument to be anchored by the device 100. For example, duringinstallation of the anchor device 100, the anchors 140 a and 140 b aredirected toward the penetration point 32 through which the catheter 20passes. When the tines 145 a and 145 b are deployed in the subcutaneousregion 34, the cap assembly 130 can be removably coupled to the base110, which transitions the anchor device 100 to the closedconfiguration. As shown in FIGS. 4A-4B, openings 104 and 105 can bedefined by the base 110 and the cap assembly 130 when arranged in theclosed configuration. As such, the catheter 20 can extend though thechannel 122 when the anchors 140 a and 140 b are deployed under the skin30.

In some embodiments, the anchor device 100 can be transitioned from theopen configuration (FIGS. 2-3) to the closed configuration (FIGS. 4A-4B)when the cap assembly 130 is coupled to the base 110. For example,during installation, the base 110 can be guided so that the anchors 140a and 140 b are directed through the penetration point 32 through whichthe catheter 20 passes. When the tines 145 a and 145 b are located inthe subcutaneous region 34 securing the anchor device 100 relative tothe skin 30 (see FIG. 1), the cap assembly 130 can be removably coupledto the base 110 to secure the catheter 20 relative to the anchor device100, thus securing the catheter 20 relative to the skin 30. In someembodiments, features of the anchor device 100 can removably couple thebase 110 to the cap assembly 130. In the example depicted in FIG. 3, thecap assembly 130 can be moved toward the base 110 (e.g., in thedirection depicted by arrow 106) to direct the tabs 112 toward to theopenings 132. When the diagonal faces of the tabs 112 contact theperimeters 134, the tabs 112 are stressed such that the tips 115 of thetabs 112 move closer to each other. When the face 135 moves beyond theengagement fingers 116, the tabs 112 can outwardly toward theirunstressed positions to releasably engage the perimeters 134. When inthis closed configuration, the cap assembly 130 and base 110 can apply acompressive force from the gripping members 120 and 135 to the catheter20 in the channel 122, thereby applying a frictional holding force tothe catheter 20 or medical instrument therein.

In some embodiments, the holding force that secures the catheter 20 tothe anchor device 100 can be released by separating the cap assembly 130from the base 110. The cap assembly 130 can be separated from the base110 by disengaging the locking tabs 112 from the cap assembly 130. Forexample, the base 110 can be separated from the cap assembly 130 byapplying pressure to the locking tabs 112 to move the tips 115 closer toeach other. When the engagement portions 116 of the tabs 112 move insidethe openings 132 in the cap 131, the retainer portions 120 and 135 forcethe cap assembly 130 away from the base 110 and the cap assembly 130becomes decoupled from the base 110, thus transitioning the anchordevice 100 to the open configuration (FIGS. 2-3). When the anchor deviceis in the open configuration, the catheter 20 can be moved relative tothe anchor device 100.

Referring now to FIG. 5 (which depicts the base 110 without the firstgripping member 120), some embodiments of the base 110 can includefeatures that facilitate assembly of the anchors 140 a and 140 b to theretainer body 111. The anchors 140 a and 140 b can be coupled to theretainer body 111 via one or more posts 117 in the retainer body 111 andcorresponding openings 143 in the anchors 140 a and 140 b. For example,during manufacturing, the anchors 140 a and 140 b can be located suchthat the posts 117 occupy the openings 143, and an overmolding processcan be used to secure the anchors 140 a and 140 b relative to theretainer body 111.

The anchors 140 a and 140 b may comprise a material that exhibitssuperelasticity when used in a patient's body. When the tines 145 a and145 b of anchors 140 a and 140 b are stressed by insertion through theskin penetration point 32, the tines 145 a and 145 b cansuperelastically flex from an expanded position (see FIG. 2) to apartially contracted position (see FIG. 10). In this partiallycontracted position, at least a portion of the tines 145 a and 145 b mayflex against the anchor shafts 141 a and 141 b. While against the anchorshafts 141 a and 141 b, the tines 145 a and 145 b can readily penetratethrough the skin penetration point 32 (which may be generally smaller inwidth than the width occupied by the tines 145 a and 145 b in a fullyexpanded state). Such a feature can reduce the damage to the patient'sskin 30 during deployment of the anchors 140 a and 140 b. In anotherexample, as described in more detail below in connection with FIGS.8A-8C, features of the anchor device 100 can cooperate withcorresponding features in the delivery tool 150 so as to minimize thelikelihood of damage to surrounding tissue when the anchors 140 a and140 b are deployed into the subcutaneous region 34. As depicted in FIG.10, the delivery tool 150 can minimize damage by holding at least aportion of the tines 145 a and 145 b against the anchor shafts 141 and141 b as the anchors 140 a and 140 b pass through the skin penetrationpoint 32.

In some embodiments, at least a portion of the anchors 140 a and 140 b(including the tines 145 a and 145 b) may be formed from a length ofnitinol wire or from a sheet of nitinol material, which has beenprocessed to exhibit superelasticity below or at about a normal humanbody temperature, such as below or at about 37 degrees C. The nitinolmaterial may comprise, for example, Nickel Titanium (NiTi), NiobiumTitanium (NbTi), or the like. Alternatively, the anchors 140 a and 140 bmay comprise a metal material such as stainless steel (e.g., 304stainless, 316 stainless, custom 465 stainless, and the like), springsteel, titanium, MP35N, and other cobalt alloys, or the like. In anotheralternative, the anchors 140 a and 140 b may be formed from a resilientpolymer material. In some embodiments, the anchors 140 a and 140 b canbe formed from a material or materials that allow the tines 145 a and145 b to be flexed to a contracted position (e.g., as in FIG. 10) andcan resiliently return to an expanded position (e.g., as in FIG. 5).

Referring now to FIGS. 5-7, the anchor device 100 can include featuresthat allow the individual anchors 140 a and 140 b to be moved relativeto each other so as to facilitate removal of the anchor device 100 fromthe skin 30. In some embodiments, the anchor device 100 comprises afoldable design in which a first portion of the base 110 is pivotablycoupled to a second portion of the base 110. For example, the anchordevice 100 can include a left portion 101 a and a right portion 101 b(refer to FIGS. 6-7), which can be flexibly pivoted with respect to eachother along a fold line 113 extending longitudinally through theretainer body 111. The left portion 101 a can include a left retainerbody portion 114 a fixedly coupled to the anchor 140 a, and the rightportion 101 b can include a right retainer body portion 114 b fixedlycoupled to the anchor 140 b. Thus, when the left and right retainer bodyportions 114 a and 114 b are pivoted about the fold line 113, the twoanchors 140 a and 140 b likewise pivot relative to one another. Thisprocess of folding the anchor device 100 can cause the anchor device 100to transition from a deployed configuration (shown in FIG. 2) where thetines 145 a and 145 b are oriented to extend in opposing directions,through an intermediate configuration (shown in FIG. 6), and to aremoval configuration (shown in FIG. 7) where the tines 145 a and 145 bare generally adjacent to each other and oriented to extend insubstantially the same direction. As described in more detail below inconnection with FIGS. 14-15, folding the anchor device 100 into theremoval configuration permits the anchors 140 a and 140 b to bemaneuvered in a manner that reduces the likelihood of the tines 145 aand 145 b causing damage to the skin 30 during removal.

The left and right retainer body portions 114 a and 114 b can comprise abiocompatible polymer material (e.g., PVC, polypropylene, polystyrene,or the like). In such embodiments, the retainer body 111 can be formedusing a molding process in which the retainer body 111 is overmoldedaround a portion of the anchors 140 a and 140 b. For example, the anchor140 a can include the opening 143. During the manufacture of theretainer body 111, at least a portion of the anchor 140 a, including theopening 143 a, 140 a can be positioned inside of an injection mold forthe retainer body 111 such that when a polymer is injected to the mold,the polymer material can flow through the opening 143 a forming one ofthe posts 117 to thereby couple the retainer body 111 to the anchor 140a. It should be understood from the description herein that the anchor140 b can also be coupled to the retainer body 111 in a similarovermolding process. It should also be understood that there exist manymanufacturing processes that can secure the anchors 140 a and 140 b tothe retainer body 111. In some embodiments, the retainer body 111 andthe anchors 140 a and 140 b can be manufactured as a single piece.

Still referring to FIGS. 5-7, the left portion 101 a of the base 110 andthe right portion 101 b of the base 110 can be formed as a singlecomponent that is bendable along the fold line 113. For example, theretainer body 111 can be configured to resiliently maintain the shapedepicted in FIG. 5. The base 110 can be transitioned from the deployedconfiguration depicted in FIGS. 2-3 to the removal configurationdepicted in FIG. 7 (e.g., when the user desires to remove the anchordevice 20 from a patient). At such time, the user may annually apply abending moment 102 (FIGS. 7-8) to fold the anchor device 100 along thefold line 113, thus causing the anchor device 100 to transition from thedeployed configuration shown in FIGS. 2-3 (where the tines 145 a and 145b are substantially oriented in opposing directions) to the removalconfiguration shown in FIG. 7 (where the tines 145 a and 145 b aregenerally adjacent to each other and oriented in substantially the samedirection). In the depicted embodiment, the tines 145 a and 145 b can berotated about 75-degrees to about 105-degrees, and preferably about90-degrees, during the transition to the removal configuration.

In some embodiments, the anchor device 100 may be deployed with acorresponding delivery device 150 (described in more detail below inconnection with FIGS. 8A-C). In alternative embodiments, the anchordevice can be deployed without the need for a corresponding deliverytool. In such circumstances, portions of the anchor device 100 (e.g.,the tines 145 a and 145 b) can be deployed in the subcutaneous region 34without the use of the delivery tool 150. For example, an IV line caninserted into a skin penetration point and then secured to in placerelative to that penetration point in a similar manner as depicted inFIG. 1. The base 110 can be grasped by a user and maneuvered toward theskin 30. When the tips 142 of the anchors 140 a and 140 b enter apenetration point, the surrounding skin supplies the force required toflex the tines 145 a and 145 b against the anchor shafts 141 a and 141b. In some embodiments, the anchors 140 a and 140 b (including the tines145 a and 145 b) can comprise a flexible polymer material. The polymermaterial can be configured to allow the tines 145 a and 145 b to flexagainst the anchor shafts 141 a and 141 b without the use of adeployment tool 150 and to minimize damage to the skin surrounding thepenetration point 32.

Referring now to FIGS. 8A-8C, in some embodiments, the anchor device 100and a corresponding delivery tool 150 can be arranged in a shippingconfiguration as part of a kit. For example, the base 110 can be locatedinside an internal cavity 152 of the delivery tool 150 while the capassembly 130 is separately coupled to the delivery tool 150. Thedelivery tool 150 can include an outer housing 160 and a device tray 170that are slidably coupled to each other to define the internal cavity152. The delivery tool 150 can incorporate features to secure the base110 and the cap assembly 130 in the kit. For example, the cavity 152 ofthe delivery tool 150 can secure the base in the package before it isprepared for deployment. Also, the cap assembly 130 can mate with tabsextending from the outer housing 160 of the delivery tool 150. After thetines 140 a-b of the base 110 are deployed in the subcutaneous layer 34of skin, the delivery tool 150 can be decoupled from the base 110. Thecap assembly 130 can be separated from the delivery tool 150 (e.g., in amanner similar to the removal of the cap assembly 130 from the base 110as described in connection with FIG. 4) and later removably coupled tothe base 110 (to secure the position of the catheter 20 relative to thebase 110). For example, in the shipping configuration depicted in FIGS.8A-8C, the anchor base 110 can be retained in the internal cavity 152 bya lip 162 of the outer housing 160 and the shape of a distal opening 174in the device tray 170. In this example, the lip 162 of the outerhousing 160 can retain a portion of base 110 by overlapping a portion ofthe base 110 and restricting the movement of the proximal portion 103 ofthe anchor device 100. As can be seen in FIGS. 8A and 8C, the distalopening 174 can allow the anchors 140 a and 140 b to protrude from thedevice tray 170 while tabs 175 cooperate with the tines 145 a and 145 bto slidably couple the base 110 to the device tray 170. In someembodiments, a user can grasp the delivery device 150 by placing theindex finger on the lower grip 164 and the thumb on the upper grip 166of the outer housing 160. To insert a portion of the anchor device 100in the skin 30, the distal opening 174 in the insertion device 150 canbe positioned adjacent to the skin penetration point 32.

In some embodiments, the tines 140 a-b of the base 110 can deploy fromthe delivery device 150 by applying a pushing force 104 can to the outerhousing 160 (e.g., by a user) while an opposing force 105 (e.g., appliedby the skin 30, a user, or a combination thereof) acts on the tray 170.As forces 104 and 105 are applied, the outer housing 160 moves generallyin the direction of force 104, relative to the device tray 170. Theportion of the outer housing 160 abutting the base 110 can cause thebase 110 to move in the direction of the force 104, relative to thedevice tray 170 and can cause the anchors 140 a and 140 b to protrudefrom the distal opening 174. Structures defined by the outer housing 160and the device tray 170 may retain the base 110 within the cavity 152until the tines 145 a and 145 b are fully deployed outside of the cavity152. While translating within the cavity 152, the base 110 can beretained in the cavity 152 by the cooperation of the lip 162 with theretainer body 111 and the cooperation of the tines 145 a and 145 b withthe tabs 175. When the tines 145 a and 145 b deploy outside of thecavity 152, the anchors 140 a and 140 b are free to move out of thecavity 152 (through channel 176), thus releasing the base 110 from thedevice tray 170. Once free from the device tray 170, the base 110 canmove relative to the outer housing 160, thereby releasing from the outerhousing 160. When the base 110 is decoupled from the housing 160 and thetray 170, the delivery device 150 can be removed, allowing the base 110to remain in place (e.g., with the anchors 140 a-b in the subcutaneouslayer 34 of skin). The cap assembly 130 can be lifted from the deliverytool 150 and coupled to the base 110 to secure the catheter 20, forexample, in a selected position relative to a patient's skin.

Referring now to FIGS. 9-15, in use, the anchor device 100 can be usedto retain a medical instrument 20, such as a catheter, in an operativeposition relative to a skin incision. As previously described, theanchor device 100 and the delivery tool 150 can include features tofacilitate the deployment of at least a portion of the anchor device 100in the subcutaneous layer 34 of a patient. In some embodiments, the skinpenetration point 32 can be surgically opened in the skin 30 so that thecatheter 20 can be inserted through the penetration point 32, throughthe subcutaneous region 34, and into a targeted vein 40 or other bodilylumen. After the catheter 20 is inserted, the anchor device 100 can bedeployed to secure the catheter 20 relative to the penetration point 32.

Referring now to FIG. 9, the anchor system 10 (e.g., including theanchor device 100 and the delivery device 150 depicted in FIGS. 8A-8C)can be guided until the distal opening 174 of the delivery device 150 isadjacent to the skin penetration point 32 that is occupied by thecatheter 20. Once in this location, the user can apply a pushing force(refer to force 104 in FIGS. 8A-B) to the outer housing 160 with anopposing force (refer to force 105 in FIGS. 8A-B) away from the skin 30applied by the skin 30 against the front face 156 of the insertiondevice 150 to deploy the tines 145 a-b of the base 110. During thisapplication of the pushing force, the outer housing 160 can move towardthe skin 30 while the front face remains substantially abutting the skin30 adjacent to the skin penetration point 32.

Referring now to FIG. 10, as the outer housing 170 moves relative to thedevice tray 160 toward the skin 30, the base 110 can translate withinthe cavity 152 and the tips 142 of the anchors 140 a and 140 b can exitthrough the opening 174 in the front face of the delivery device 150 andinto the skin penetration point 32 (e.g., through the same incisionthrough which the catheter 20 was previously inserted). As the anchors140 a and 140 b exit the insertion device 150, the tines 145 a and 145 bmay flex against the shafts 141 and 141 b of the anchors 140 a and 140 bdue to the force applied by the sides of the opening 174. By resilientlyflexing against the anchor shafts 141 a and 141 b, the tines 145 a and145 b can pass through the penetration point 32 in a way that reducesthe likelihood of damage to the tissue surrounding the penetration point32. As the anchors 140 a and 140 b exit the insertion device 150 throughthe opening 174, the tines 145 a and 145 b can advance into thesubcutaneous layer 34. The tines 145 a and 145 b can be biased to returntoward the deployed configuration, as previously described in connectionwith FIGS. 2-3.

Referring now to FIG. 11, after the anchors 140 a and 140 b penetratethe skin 30 so that the tines 145 a and 145 b pass into the subcutaneousregion 34, the tines 145 a and 145 b can resiliently return toward thedeployed configuration in which the first tine 145 a extends outwardlyaway from the second tine 145 b. The curved shape of the tines 145 a and145 b can allow them to deploy adjacent to and abut the underside of theskin 30 to anchor the device 100 relative to the skin without tearingthe dermal layers 36. As described previously in connection with FIGS.8A-8C, once the tines 145 a and 145 b have deployed from the deliverytool 150, the deployment device 110 can become decoupled from thedelivery tool 150.

Referring now to FIGS. 12-13, to retain the catheter 20 in an operativeposition, the catheter can be positioned along the channel 122 of theretainer portion 120. The user can decouple the cap assembly 130 fromthe delivery tool 150 and press the cap assembly 130 to the base 110 tocompress the retainer portions 120 and 135 onto the outer surface of thecatheter 20 (to provide a frictional holding force thereon), thustransitioning the anchor device 100 to the closed configuration. Toreposition the catheter 20, the cap assembly 130 can be separated fromthe base 110 by applying pressure to the locking tabs 112 to move thetips 115 closer to each other until the cap assembly 130 is separatedfrom the base 110, thus transitioning the anchor device 100 to the openconfiguration (refer to FIGS. 2-3). As the catheter 20 is no longersecured in place by the anchor device 100, it can be repositioned(advanced distally or withdrawn proximally) before being secured onceagain to the anchor device 100 by coupling the cap assembly 130 to thebase 110. Optionally, a flexible sleeve 108 can be fit over the catheter20 if the outer diameter of the catheter 20 is too small to releasablysecure inside the channel 122 of the retainer portion 120. The flexiblesleeve 108 may comprise a silicone material or another polymer materialso that a compression force applied to the sleeve 108 creates a frictionholding force upon the catheter 20. The sleeve 108 may be provide aspart of the kit described in connection with FIGS. 8A-C and may bereleasably secured to the delivery device 150 during shipment.

Referring now to FIG. 14, when the catheter 20 is ready to be withdrawnfrom the patient, the catheter 20 can be withdrawn from the patientseparately from the anchor device 100. In one example, after a catheterprocedure is complete, the cap assembly 130 can be separated from thebase 110, thus allowing the catheter 20 to be lifted away from thechannel 122 of the flexible portion 120. After the catheter 20 isdissociated from the anchor device 100, the catheter 20 can be removedfrom the skin 30 by application of a withdrawal force 26 (while the base110 remains coupled to the skin 30).

As previously described, the left portion 101 a of the anchor device 100can be pivoted with respect to the right portion 101 b before removingthe anchors 140 a and 140 b from the subcutaneous region 34 under theskin 30. In some embodiments, the left retainer body portion 114 a andthe right retainer body portion 114 b are manufactured as an integralpiece with a flexible fold line 113 (along a central longitudinal axisin this embodiment). As such, the body portions 114 a and 114 b can bepivoted with respect to each other while the anchor tines 145 a and 145b are deployed in the subcutaneous region 34 (refer to FIG. 14).Accordingly, the anchors 140 a and 140 b (including the tines 145 a and145 b) can collectively penetrate into the subcutaneous region 34 in aconfiguration depicted in FIG. 11, and may be pivoted into the removalconfiguration shown in FIG. 14 for withdrawn from skin penetration point32. In some embodiments, two portions 101 a and 101 b of the base 110can be pivoted to the removal configuration so as to reduce thelikelihood of trauma to the skin 30 surrounding the penetration point 32during removal of the anchors 140 a and 140 b. In some circumstances,the folded anchor device 100 can be maneuvered as to reduce the crosssectional area of the portion of the anchors 140 a and 140 b beingwithdrawn through the dermal layers 36, thus reducing the likelihood ofdamaging the surround skin tissue during removal of the anchors 140 aand 140 b (refer to FIG. 14).

Referring now to FIG. 15, the anchor device 100 can be removed from thepatient's skin 30 in a manner that contemporaneously withdraws theanchor tines 145 a and 145 b in a generally side-by-side arrangement. Asdescribed previously in connection with FIG. 14, the anchor device 100can be folded such that the anchors 140 a and 140 b are adjacent to eachother and oriented in substantially the same direction (e.g., the tips146 of the tines 145 a and 145 b may be shifted proximate to oneanother). The anchor device 100 can be maneuvered to simultaneouslyremove the anchors 140 a and 140 b from the skin 30. For example, whenthe tines 145 a and 145 b are pivoted to the side-by-side arrangement,the user may apply an upward force 149 that lifts the anchors 140 a and140 b away from the skin (with the tips 146 of the tines 145 a and 145 bbeing at the trailing end). Such a removal process can be used to reducethe cross sectional area of the portion of the anchors 140 a and 140 bbeing withdrawn through the dermal layers 36, thereby reducing thelikelihood of damaging the surrounding skin tissue during removal of theanchors 140 a and 140 b. It should be understood from the descriptionherein that, in some embodiments, the anchor device 100 can be removedfrom the skin 30 (e.g., in a manner similar to that depicted in FIGS.14-15) while the catheter 20 remains in the skin 30.

A number of embodiments of the invention have been described.Nevertheless, it will be understood that various modifications may bemade without departing from the spirit and scope of the invention.Accordingly, other embodiments are within the scope of the followingclaims.

What is claimed is:
 1. An anchor system for securing the position of a medical instrument, comprising: a delivery device to advance an anchor device toward a skin penetration point that is occupied by a medical instrument, the delivery device defining an internal space and a distal opening; and the anchor device being deployable from the internal space of the delivery device and comprising: a retainer base to releasably secure with the medical instrument, and one or more subcutaneous anchors that extend distally from the retainer base and toward the skin penetration point when the delivery device deploys the one or more subcutaneous anchors from the distal opening, each anchor comprising a tine that deploys in a subcutaneous region to secure the retainer base relative to the skin penetration point, wherein each tine is pivotable about a longitudinal axis from a deployed configuration to a removal configuration.
 2. The anchor system of claim 1, wherein the retainer base is separable from the delivery device when the delivery device deploys the one or more subcutaneous anchors from the distal opening.
 3. The anchor system of claim 1, wherein the one or more anchors extend distally from the retainer base such that the retainer base is arranged external to the skin penetration point when the tine is deployed in the subcutaneous region.
 4. The anchor system of claim 1, wherein a first body portion of the retainer base is pivotable about a fold line relative to a second body portion of the retainer base while the first and second body portions remain physically coupled to one another, and the anchors comprise a first anchor coupled to the first body portion and a second anchor coupled to the second body portion.
 5. The anchor system of claim 4, wherein the first body portion and the second body portion of the retainer base are formed as a single component that is bendable along the longitudinal axis so as to pivot the first body portion relative to the second body portion.
 6. The anchor system of claim 4, wherein the flexible tines of the first and second anchors are rotated about 75-degrees to about 105-degrees when the first and second anchors are adjusted from the deployed configuration to the removal configuration.
 7. The anchor system of claim 1, the one or more subcutaneous anchors comprise a metallic material that exhibits superelasticity when used in a human body.
 8. The anchor system of claim 1, wherein the medical instrument comprises a catheter, further comprising a flexible sleeve to fit over a portion of the catheter when the retainer base releasably secures with the catheter.
 9. An anchor system for securing the position of a medical instrument, comprising: an anchor device configured to releasably secure to an external portion of a medical instrument while another portion of the medical instrument occupies a skin penetration point, the anchor device including: a retainer base to releasably secure with the external portion of the medical instrument, and one or more subcutaneous anchors that extend distally from a distal end of the retainer base and toward the skin penetration point, each anchor comprising: a longitudinal shaft portion that extends distally from the distal end of the retainer base, and a flexible tine that deploys in a subcutaneous region to secure the retainer base relative to the skin penetration point, wherein each tine is pivotable about a longitudinal axis define by a longitudinal hinge of the retainer base from a deployed configuration to a removal configuration.
 10. The anchor system of claim 9, further comprising a delivery device to advance the anchor device toward the skin penetration point, the delivery device defining an internal space and a distal opening, the anchor device being deployable from the internal space of the delivery device.
 11. The anchor system of claim 10, wherein the retainer base is separable from the delivery device when the delivery device deploys the one or more subcutaneous anchors from the distal opening.
 12. The anchor system of claim 9, wherein the one or more anchors extend distally from the distal end of the retainer base such that the retainer base is arranged external to the skin penetration point when the tine is deployed in the subcutaneous region.
 13. The anchor system of claim 9, wherein a first body portion of the retainer base is pivotable about the longitudinal hinge relative to a second body portion of the retainer base while the first and second body portions remain physically coupled to one another, and the anchors comprise a first anchor coupled to the first body portion and a second anchor coupled to the second body portion.
 14. The anchor system of claim 13, wherein the first body portion and the second body portion of the retainer base are formed as a single component that is bendable along the longitudinal axis so as to pivot the first body portion relative to the second body portion.
 15. The anchor system of claim 13, wherein the flexible tines of the first and second anchors are rotated about 75-degrees to about 105-degrees when the first and second anchors are adjusted from the deployed configuration to the removal configuration.
 16. The anchor system of claim 9, the one or more subcutaneous anchors comprise a metallic material that exhibits superelasticity when used in a human body.
 17. The anchor system of claim 9, further comprising a flexible sleeve to fit over an outer circumferential surface of the external portion of medical instrument when the retainer base releasably secures with the medical instrument. 